Method of manufacturing composite metal



June 7, 1938. v H. QUPRE 2,119,668

METHOD OF MANUFACTURING COMPOSITE METAL June 7, 1938. v H, DUPRE v 2,119,668

METHOD OF MANUFACTURING COMPOSITE METAL ATTORNEY Patented June 7, 1938 UNITED STATES METHOD OF MANUFACTURING COMPOSITE METAL Valentine H. Dupr, Oak Park, Ill., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application June 7,

8 Claims.

This invention relates to methods of manufacturing composite metal supporting devices, and more particularly to methods of manufacturing mounting plates for coin collecting apparatus.

An object of this invention is the provision of improved, inexpensive methods of manufacturing composite metal supporting devices, such as mounting plates for coin collecting apparatus.

In accordance with the above object the invention contemplates methods of manufacturing a non-frangible mounting plate for coin collectors comprising a strip steel frame having the desired contour and united at its abutting ends within which is die cast a base portion having several details, mounting lugs, and apertures, the steel frame being provided with a series of suitably spaced apertures, or in its inner periphery with depressions, perforated lugs, continuous or intermittent dovetail grooves, slots or other suitable means to securely anchor the frame to the die cast base portion. To further strengthen the cast base portion spaced steel ribs having perforations and/or perforated lugs or other means. eX- tending therefrom to securely anchor them are engaged at their ends in notches formed in the inner periphery of the steel frame, or in inwardly extending lugs, the die cast base portion being cast around the anchoring means and a portion of the ribs.

Other objects and advantages of this invention will more fully appear from the following detailed description taken in conjunction with the accompanying drawings, wherein Fig. 1 is a front elevational view of an improved reinforced composite metal mounting plate for coin collecting apparatus produced in accordance with one method of this invention;

Figs. 2 and 3 are side and bottom plan views, respectively, of the mounting plate illustrated in Fig. 1;

Figs. 4 and 5 are enlarged horizontal and vertical sections taken on the lines 4-4 and 5 5, respectively, of Fig. 1;

Fig. 6 is a fragmentary front elevational vleW of a modified form of mounting plate;

Fig. '7 is a horizontal section taken on the line 'I-'I of Fig. 6;

Fig. 8 is a fragmentary plan view of Fig. 6 showing an alternative means for uniting the frame and ribs;

Fig. 9 is a vertical section taken on the line 9--9 of Fig. 8, and

Fig. 10 is a section similar to that of Figs. 4 and 7 illustrating a further modification of the invention.

1935, serial No. 25,385

(Cl. 22a-148.2)

A reinforced composite metal back or mounting plate for coin collecting apparatus may be produced according to the following method. Referring to the drawings, particularly to the embodiment of the invention illustrated in Figs. 1

to 5, lncluslve, the mounting plate shown comprises a peripheral or outer steel frame or shell I extending around a die cast baseportion I6 and a series of vsteel ribs I'I extending longitudinally thereof.

The frame I5 is formed from flat strip steel stock of the required dimensions and cut out at its forward left hand edge (Fig. 1), as indicated at I 8 and I9, and at its rearedge at opposite ends as indicated at 22 (Fig. 3) for use in the completed coin collecting apparatus. At predetermined spaced points around the four sides of the frame I5 there is formed circular tapered or countersunk apertures 23, the largest diameter of the apertures being at the outer surfaces of the frame. The apertures 23, as will be presently described, serve to securely anchor the frame I5 to the die cast base portion I6. Instead of apertures 23 extending through the thickness of the strip forming the frame I5, depressions extending from the inner peripheral surface of the frame part way through the thickness of the strip may be employed for anchoring the frame to the cast base portion I6. Also formed in the frame I5 in its inner peripheral surface and at opposite ends are slots 24 for receiving the opposite ends of the ribs I'I. The slots as clearly shown in Fig. 5 extend from the bottom edge of the frame I5 with which the lower edges of the ribs are alined to the top of the ribs.` It is understood that the several cutouts I8, I9 and 22, apertures 23, 'or depressions, and slots 24, are formed in the frame strip whileit is in flat strip form in a manner well known in the metalworking art. The frame strip is then shaped upon a suitable forming xture, to provide a desired contour for the mounting plate as shownin Fig. 1 and the abutting ends of the strip, as indicated at 25 are then electrically welded or otherwise integrally united. Instead of a single strip the frame I5 may be constructed from several strips extending around the Abase portion I6 and united at suitable points.

The ribs I'I, like the frame l5, are formed from flat strip steel stock of the required dimensions and cut away along one side to provide a series 50 of suitably spaced lugs 26 which maybe perforated as indicated at 21 simultaneously with their forming. Thereafter the lugs 26 are bent at right angles to thebody of the ribto form the completed rib I'I, clearly shown in Figs. '4 and 5. 55

in the completed mounting plate the lugs 26 and apertures 21 serve to securely anchor the ribs I1 to the die cast base portion I6.

After positioning the ribs I1 in the slots 24 of the frame I5, the assemblage is placed in a suitable die or mold, which is of sectional character, carried in a die casting machine, and molten die casting metal known in the market as Zamak, or any other suitable die casting metal, is then injected into the die under pressure in a manner well known in the art and the die is filled with the molten metal. The metal flows into every recess cr space in the die thereby producing a true casting corresponding to the die cavity including the space provided by the apertures 23 in the steel frame I5 and the apertures 21 in the steel ribs thus producing an integral structure comprising the steel frame I5, cast base portion I6 and the ribs I1.

In the die casting of the base portion I6 it is provided with a plurality of mounting lugs or details 29, 38, 34 and 32 and a housing 33, such details serving in the completed telephone coin collecting apparatus of which the reinforced composite die cast mounting plate is a part to support and house certain details of the apparatus. The cutouts 22 in the steel frame I5 at opposite ends of the rear edge, hereinbefore described, provide a space for the entrance of electrical conductors, Which extend in some cases from above and in other cases from below the apparatus, to the rear of the apparatus and then are passed through a circular aperture 34 formed in the cast base portion I6 during its casting. The aperture 34 is also used for injecting the molten metal during the casting operation into the die cavity. At predetermined points throughout the cast base portion lI6 circular hollow bosses 35 are cast therein Which extend rearwardly or from the back face thereof, the hollows of the bosses being countersunk at their inner ends, for the purpose of receiving screws for attaching the telephone coin collecting apparatus carried by the mounting plate to -a supporting plate (not shown) which in turn is Xed to a vertical wall of a room or booth. Also formed in the cast base portion I6 during the casting thereof are a plurality of apertures 35 which are used in assembling certain parts of the telephone coin collecting apparatus.

In Figs. 6 and '1 another embodiment of the invention is illustrated, wherein a peripheral frame 31 is made from steel stock having a T shaped cross-section throughout its length, the center arm of the stock being operated upon while n flat form by punch and die and perforating mechanism to form a series of predeterminately spaced lugs 38 having perforations 39 extending therethrough. In another forming operation the stock may be worked to provide cutouts and slots similar to the cutouts I8, I9 and 22 and slots 24 described in connection with the embodiment shown in Figs. l to 5, inclusive. The lugs 38 and the 'perforations 39 therein of the frame 31 serve in the completed mounting plate to securely anchor the frame to a cast base portion 4U cast within the frame which also carries longitudinally extending steel ribs 4I, similar to the ribs I1 of the back plate shown in Figs.V 1 to 5, inclusive. VOther than the use of the perforated lugs 38 extending from the inner peripheral surface of the frame 31 foranchoring the frame to the cast base portion 48 and the thickening lof the cast base portion surrounding the-lugs the two described reinforced composite die cast mounting plate constructions and the method of producing them are identical.

Figs, 8 and 9 illustrate an alternative means for uniting the frame 31 and ribs 4I of the construction shown in Figs. 6 and '1 wherein the perforated lugs 38 at opposite ends of the frame are slightly extended toward the longitudinal center line thereof and notched at 42 to receive the ends of the ribs 4I.

The embodiment of the invention shown in Fig. l0 consists in forming ya peripheral frame 44 from flat strip steel stock which is Worked to provide a continuous dovetail groove 45 in one of its side surfaces, the strip then being formed into the frame with the grooved side surface forming the inner periphery thereof. Longitudinally extending steel ribs 46 are included in this embodiment which are cut from iiat stock and perforated, as indicated at 41, at spaced points along their length. In the casting of a base portion 48 within the frame 44 the dovetail groove 45 serves to anchor the frame to the cast base portion and the` thickening of the cast base portion surrounding the upper perforated portion and entered in the apertures 41 of the ribs 46 serves to anchor the ribs to the cast base portion. With the exception of the manner' of anchoring the frame 44 and the ribs 46 to the cast base portion 46 the reinforced die cast mounting plate construction shown in Fig. and the method of manufacturing it is identical to the mounting plates shown in Figs. 1 to '7, inclusive.

Although the frame 44 is described as being formed with a continuous dovetail groove in its inner periphery it will be obvious that the groove may be intermittently formed therein.

From the above description it will be apparent that by practicing the methods of this invention a non-frangible reinforced composite metal mounting plate for coin collecting apparatus may be economically and eiciently produced, the parts being integrally united in such a manner that a sturdy and Ydurable mounting plate is effected. By casting the base portion within a steel frame which surrounds its periphery and securely anchoring it thereto and reinforcing it by steel ribs united to the frame and also securely anchored to the cast base portion., the cast portion is fully protected when assembled with the coin collecting apparatus and when in use from being cut or burned away or otherwise tampered with in an effort to pilfer coins from the apparatus. Furthermore, as is well known in the art the die cast lbase portion requires practically noV machining except to cut off the usual sprue left on the casting whereY the molten metal is injected into the die cavity.

Although the embodiments of this invention las herein illustrated and described are particularly well adapted for use in connection with telephone coin collecting apparatus, it should be understood that the invention is capable of other applications and should be limited only by the scop-e of the appended claims.

What is claimed is:

1. The method 'of making composite metal mounting plates for coin collectors or the like comprising shaping a perforated metal strip into a frame of the desired contour for the mounting plate, placing the frame in a die, and then injecting molten die casting metal into the die cavity and within the inner periphery of the frame Vand'into the perforations .provided in the frame to interlock the 'frame tothe cast .portion.

2. The -method of making composite metal mounting plates for coin collectors or the like comprising shaping a metal strip into a frame of the desired contour for surrounding tlie entire peripheral surface of the mounting plate, uniting the ends of the strip forming the frame, placing the frame in a die, and then injecting molten die casting metal into the die casting cavity and Within the inner periphery of the frame and into engagement with cooperating surfaces provided on the frame to interlock the frame to the cast portion.

3. The method of making composite metal mounting plates for coin collectors or the like comprising forming in a metal strip a plurality of depressed surfaces, shaping the strip into a frame of the desired contour for the mounting plate, molecularly uniting the ends of the strip in abutting relation, placing the frame in a die, and then injecting molten die casting metalV into the die casting cavity to surround the inner periphery of the frame and into engagement With the depressed surfaces thereof to interlock the frame to the cast portion.

4. The method of making composite metal mounting plates for coin collectors or the like comprising forming on a metal strip a plurality of perforated lugs projecting from one side thereof, shaping the strip into a frame of the desired contour for the mounting plate, the perforated lugs being positioned inside the frame, uniting the ends of the strip forming the frame, placing the frame in a die, and then injecting molten die casting metal into the die casting cavity and within the inner periphery of the frame, surrounding the perforated lugs, and entered in the perforations of the lugs to interlock the frame to the cast portion.

5. The method of making composite meta mounting plates for coin collectors or the like comprising shaping a metal strip into a frame of the desired contour for the mounting plate with a plurality of reinforcing metal ribs Within the inner periphery of and united thereto, placing the framein a die, and then injecting molten die casting metal into the die cavity and Within the inner periphery of the frame, surrounding a portion of the ribs, and into engagement with cooperating surfaces provided on the frame to interlock the frame to the cast portion.

6. The method of making composite metal mounting plates for telephone coin collectors or the like comprising forming in a metal strip a plurality of tapered perforations, shaping the strip into a frame of the desired contour for they mounting plate with thev largest diameter of the tapered perforations disposed at the outer periphery of the frame, uniting the ends of the vstrip in abutting relation, forming from metal strip a plurality of reinforcing ribs having a plurality of perforated lugs extending angularly therefrom, arranging the ribs Within the frame with their opposite ends engaged ingrooves formed in opposite inner peripheral` surfaces of the frame, placing they framein a die, and then injecting molten die casting metal into the die casting cavity and Within the inner periphery of the frame to form a cast base plate portion and entered in the tapered perforations of the frame, surrounding the perforated lugs of the ribs, and entered in the perforations of the lugs to interlock the frame to the cast base plate portion.

7. The method of making irregular rectangular shaped composite metal mounting plates for telephone coin collectors or the like comprising forming a steel frame of the desired contour for the mounting plate with a plurality of steel ribs extending longitudinally thereof within its inner periphery and united thereto, placing the frame in a die, and then injecting moltendie castingY of perforated lugs projecting from one side thereof, shaping the strip into a frame of the desired contour for the mounting plate with a plurality of reinforcing metal ribs Within' the inner periphery of and united to the frame by being entered at opposite ends in notches formed in the lugs of the frame, placing the frame in a die, and then injecting molten die casting metal into the die cavity and Within the inner periphery of the frame, surrounding a portion of the ribs, and into engagement with cooperating surfaces provided on the frame to interlock the frame and the ribs to the cast portion. Y P

' VALENTINE I-I. DUPRE. 

